1. Field of the Invention
The present invention relates to a technology to increase efficiency of cooling on a cooling device in which an axial fan motor is used.
2. Description of the Related Art
In general, a heat sink is used for effectively discharging heat out of semiconductors or the like in electronic equipment such as a personal computer or the like. Also, in order to forcibly cool the heat sink, an axial fan motor is used.
However, since the axial fan motor is provided with a motor in its central portion, the flow rate of air at the central portion is reduced in comparison with the peripheral portion of the axial fan motor so that the heat sink as a whole can not be uniformly cooled. Additionally, since the air flow from the axial fan motor forms a swirl, it is also difficult to feed cooling air sufficiently to deep portions of cooling fins of the heat sink.
Accordingly, where it is known in advance that the cooling capacity of the axial fan motor would be insufficient, the air flow from the axial fan motor is controlled so that the air flow becomes uniform. In addition, in order to provide the air without a swirl flow, an axial fan motor provided integrally with air rectification blades is used.
However, where the situation occurs in which a axial fan motor without air rectification blades is replaced by an axial fan motor provided with air rectification blades due to a later requirement to avoid the insufficiency of the cooling capacity, the replacement cost for the axial fan motors becomes high. Also, even if the axial fan motor provided in advance with the air rectification blades is used, where it is necessary to change the shape of the blade of the air rectification blades later, it is necessary to replace the axial fan motor as a whole, resulting in the same problem.
Also, it is necessary to manufacture a housing specialized for a shape of each blade needed for the axial fan motor provided with air rectification blades. Where such a housing is molded of resin, there is a problem that many kinds of molds are needed.
The present invention has been made in view of the foregoing difficulties, and therefore has an object to provide air rectification blades for later controlling the flow rate of the air from an axial fan motor as desired to thereby enhance a cooling efficiency of a cooling device using the axial fan motor. Also, another object of the present invention is to reduce cost by reducing the number of dies for the axial fan motor.
In order to attain these and other objects, according to a first aspect of the present invention, there are provided air rectification blades for controlling a flow rate of air from an axial fan motor, comprising an engagement portion that enables the air rectification blades to selectively attach to or detach from the axial fan motor. Then, the desired flow rate of air is controlled by selectively attaching or detaching the air rectification blades to or from the axial fan motor that has not been provided with any air rectification blades.
The air rectification blades according to a second aspect of the present invention further comprise an engagement portion that enables the air rectification blades to directly attach to a heat sink. Accordingly, a rectified blow of air is brought to the heat sink by a cooling device comprising an axial fan motor not provided with any air rectification blades and air rectification blades, thereby cooling the heat sink directly.
In the air rectification blades according to a third aspect of the present invention, the heat sink is used for cooling semiconductors. Accordingly, the rectified blow of air is brought to the heat sink by a cooling device comprising an axial fan motor not provided with any air rectification blades and the air rectification blades, thereby cooling the heat sink directly and enhancing the cooling efficiency of the semiconductors.
In the air rectification blades according to a fourth aspect of the present invention, the engagement portion is provided with a one-touch attachable/detachable mechanism. Namely, the attachment/detachment of the air rectification blades to the axial fan motor or the attachment/detachment of the air rectification blades to the heat sink are performed without using any tool or jig, thereby enhancing the later detachability/attachability.
In the air rectification blades according,to a fifth aspect of the present invention, the air rectification blades have a contour continuous with the axial fan motor. It is therefore possible to receive the assembly substantially in the same space for that of the prior axial fan motor provided with the air rectification blades.
The air rectification blades according to a sixth aspect of the present invention may further comprise rectification plates taking on a uniform thickness vane shape. Then, in the case where the rectification plates are made of resin, it is possible to simplify the shape of the portion of the molds for forming the rectification plates.
The air rectification blades according to a seventh aspect of the present invention may further comprise rectification plates taking on a wing shape. With such blade shape rectification plates, the vane strength of the rectification plates is enhanced. Also, the generation of sound or vibration when the air passes through the rectification plates is suppressed.